Printing-form.



H. 1. SMITH.

PRINTING FORM.

APPLICATION FILED NOV. 19, 1909 967,582. Patented Aug. 16, 19 0.

UNITED s'rnrns PATENT oFFicn.

I-IAZOR J. SMITH, OF CHICAGO, ILLINOIS, ASSIGNOR TO AUTOMATIC LETTER MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

PRINTING-FORM,

cornea Specification of LettersIE'atent. Patented Aug. 16, 1910.

Application filed November 19, 1909. Serial No. 528,880.

To all whom it may concern:

Be it known that I, HAZOR J. SMITH, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Printing-Forms, of which the following is a specification. i My invention relates to an improvemen in the art of printing, in printing-presses, from loose forms, especially where the impression is elfected by the relative rolling action of the form and platen, one against the other, and the form is printed by a pro gressive-impression action as distinguished from a single-impression action. I My invention is applicable, more especially, to printing-machines of the letterpress type, as, for example, the machine shown and described in the Smith and Woodward Patent No. 928,887, granted July 20, 1909, in which machine the printing is effected by a traveling platen, or impression roller, moving across the form from one end to the other. It may be stated that in the use of machines of this class it is usual to provide the printing-form in a chase having a base-plate, thereby avoiding the necessity of securely locking the form in the chase. In the said patented machine the impressionroller travels over the form under a pressure so regulated that when distributed over a full line it effects the desired impression;

when crossing a short line, however, it is apt to impress the same unduly into the sheet being printed and produce an unclesirable embossing effect, besides making the short line appear heavierthan the full lines. My object is to provide means whereby a loose printing-form of metal type may be caused to print a sheet with desired uniformity throughout, irrespective of variations in the area of surface contact, between sections of the form and the sheet being printed, during the progressive-impression action.

I11 carrying out my invention, I seat the type 011 a base or foundation of resilient material, which may be a sheet of soft rubber, and to obtain practical results, in the use of my invention, it is necessary that the material employed for the bed shall be more yielding than the material of which the imprinting pressure rather than impress itself unduly into the sheet being printed.

Referring to the drawingFigure 1 shows a letter-press chase provided with a sheet of resilient material forming a bed for a printing form; Fig. 2, a broken plan-view of a printing-form in the chase; and Fig. 3, a broken and enlarged section taken on line 3 of Fig.2.

The chase 4 is provided with a base-plate 5, and fitting upon the base-plate within the chase is a sheet, or bed, 6 of resilient material, such as rubber. The bed 6 may be in one piece or in sections of any desired size. The resilient quality of the material, of which the sheet 6 is composed, should be such, with relation to that of the impressionroller, or-platen, of the press, that suitably clear impressions of full lines of type will be effected in printing, and that where an uneven distribution of pressure occurs the unduly pressed type, or form-section, will yield against its bed rather than impress itself unduly into the sheet being printed. When printlng in imitation of typewriting, high periods). as they are called, may be employed to indent themselves into the sheet being printed, as occurs in actual typewriting, but the eifect in printing from a form should be such that the letters and other characters of larger area than periods, more especially, should present an even appearance throughout the sheet. By the employment of my present invention I am able to produce in a printing-machine of the letter press type printed sheets free from the defects, of uneven impressions at certain parts of the form, so common in letter-press work as hitherto produced.

I have found in practice that it is desirable, in carrying out my invention, to employ the interlocking type illustrated in Fig. 3 and which forms the subject of an application for Letters Patent, filed by me Septemher 1, 1909, and bearing Serial Number 515,586, for the reason that the resilient bed, or lining, has a tendency to cause the blank type to climb.

The printing-type 7 and blank-type 8 are provided, in the rear faces of their baseportions, with recesses terminating in overhanging shoulders 9, and the blank-type are also provided,on the forward faces of their base-portions, with projections terminating in shoulders 10. 'When a form is set up the projections of the blank type enter the recesses of the adjacent type, whereby engagement of the-underlying shoulders 10 with the overhanging shoulders 9 operates to hold the blank type against climbing.

My invention is only useiul in the case of a loose form which permits movement of the individual type relative to each other; and without'some such means as is provided by the interlocking feature of the type, as shown, blank type (which term may include spaces, quadrats, spacelines, leads, reglets, etc.) will tend to climb to the printing-plane, become inked and injure the appearance of the printed sheet. It will be noted that the overhanging shoulders of all the type are in a plane materially higher than the underlying shoulders or the blank type, which I permits limited independent movement of individual printing type whereby they may sink, sufficiently for all purposes under ,printing pressure, into the resilient bed with out obstruction from adjacent blank type.

What I claim as new, and desire to secure by Letters Patent, is

1. In combination, a loose printing-form composed of printing and blank type, and a resilient bed against which the individual printing type of the form rest to be independently yieldable under printing pressure, the blank type, to prevent its climbing to the printing plane, interlocking with adjacent printing type without thereby obstructing independent yielding of the prii'iting type.

2. In combination,.a loose printing-form composed of printing and blank type, and a resilient bed of rubber-like material against which the individual printing type of the form rest to be independently yieldable under printing pressure, the blank type, to prevent its climbing to the printing plane, interlocking with adjacent printing type without thereby obstructing independent yielding of the printing type.

3. In combination, a printers chase having a base-plate and a resilient bed on the base-plate formed of a sheet of rubber-like material, a loose printing-form in the chase comprising printing and blank type resting against said bed, the blank type, to prevent its climbing to the printing plane, interlocking with adjacent printing type without thereby obstructing independent yielding of the printing type under printing pressure.

HAZOR J. SMITH. I11 presence of- R. A. RAYMOND, J. G. ANDERSON. 

